Monday, September 15, 2014

Fall is Finally Here! Sept. 8-14th

A strong cold front pushed through this week and brought migration with it. Twenty warbler species were captured and/or observed this week including Black-and-white Warbler (BAWW), Prothonotary Warbler (PROW), Tennessee Warbler (TEWA), Nashville Warbler (NAWA), Yellow Warbler (YEWA), Magnolia Warbler (MAWA), Cape May Warbler (CMWA), Black-throated Blue Warbler (BTBW), Black-throated Green (BTNW), Blackburnian (BLBW), Chestnut-sided (CSWA), Bay-breasted (BBWA), Blackpoll (BLPW), Ovenbird (OVEN), Northern Waterthrush (NOWA), Connecticut (CONW), Common Yellowthroat (COYE), Wilson's (WIWA), Canada (CAWA), and American Redstart (AMRE). All five brown thrushes we would expect visited as well. A large push of BBWAs and MAWAs arrived on 13 September following the cold front with most leaving that evening as numbers dropped off considerably on Sunday. BLPWS continue to pick up, and a pleasant surprise of a returning banded adult female Blackpoll Warbler from fall 2013 was recorded. Further support that the Lake Erie Marsh Region is important to this long distance migrant.

Blackpoll and Bay-breasted Warblers can be difficult to tell apart in fall plumage. The opportunity to have the birds in hand, with a good view of different field marks, can assist you in identifying more BBWAs and BLPWs in the field.

BBWA left BLPW right
 Note the dark streaking on the BLPW flanks and back whereas the BBWA has comparatively little. The photo below shows the front of these two species and demonstrates the subtlety of the streaks on the BBWA and the more distinctive streaking of the BLPW.
BBWA left and BLPW right

Note darker and heavier streaking on the back of the BLPW 
One of the striking differences is the feet and leg coloration of the BBWA and BLPW. Surprisingly, leg color can often be observed in the field and can assist in accurate identification. While the color may not register, the light reflective color of the BLPW and dull light absorbing of the BBWA can often be picked up by your eyes providing an indication to the species. See Below:
BBWA feet and legs are a gray color when compared to BLPW below

BLPW have browner legs with yellow on the pads of the feet, which can often be seen in the field.
We do not get many of the forest resident guild along the beach ridge. Species such as Black-capped Chickadee (BCCH), White-breasted Nuthatch (WBNU), and Tufted Titmouse (TUTI) seem to avoid the lakefront for most of the year due to the lake-effect cold of the winter. However, we have seen an influx of these species over the last few years. The beach ridge may be a dispersal habitat rich in food during the critical time of fall migration.

It is easy to tell males from females on Nuthatches by their head color. Females have a pewter gray head and males have a solid black cap.
WBNU female: Note the gray cap, and the specialized bill shape for extracting insects from under tree  bark

WBNU male with black cap
The coming week should result in an increase in the numbers of Blackpolls and thrushes. With our first Ruby-crowned Kinglet showing up this week, we anticipate their arrival as well. And White-throated Sparrow numbers will begin to increase, too.

Get outside and enjoy the diversity of fall migration. Public banding demonstration is this Saturday at BSBO from 10 AM to 11:30 AM.

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